Euphorbia milii plant named ‘Apollon’

ABSTRACT

A new distinct cultivar of  Euphorbia milii  plant named ‘Apollon’, particularly characterized by its compact plant habit; dense and bushy plant form; moderate growth habit; abundant, small yellow floral cymes with yellow-green bracts; high number of flowers per plant.

Latin name of the genus and species of the plant claimed: Euphorbia milii.

Variety denomination: ‘Apollon’.

BACKGROUND OF THE INVENTION

The present Invention relates to a new and distinct cultivar of Euphorbia milii plant, botanically known as Euphorbia milii Desmoul., commonly known by the name Crown of Thorns, and hereinafter referred to by the name ‘Apollon’.

The new Euphorbia milii is a product of a planned breeding program conducted by the Inventor, Steen Thomsen, in, Haarslev, Fyn, Denmark. The new Euphorbia milii originated from a cross made in 2001 by the Inventor with unnamed cultivars of Euphorbia milii Desmoul. The male and female parental cultivars are unnamed, unpatented seedlings of Euphorbia milii Desmoul. The Inventor selected the new Euphorbia milii cultivar as a single plant from the progeny of the above cross in 2001 on the basis of flower color and compact, freely branching habit. Plants of the new Euphorbia milii are upright, compact and have a unique color combination and abundant small flowers.

Asexual reproduction of the new cultivar by terminal cuttings taken and propagated in trial production batches at Hjortebjerg Nurseries, Denmark, has shown that the unique features of this new Euphorbia milii are stable and reproduced true to type in many successive generations of asexual reproduction.

BRIEF DESCRIPTION OF THE INVENTION

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘Apollon’. These characteristics in combination distinguish ‘Apollon’ as a new and distinct cultivar:

1. Floral bract color 143C, yellow-green with a slight marginal tinge of light red 36D to light yellow green 145C.

2. Very dense and bushy plant form, mainly due to more upright stems.

3. Moderately vigorous growth habit.

4. High number of flowers per plant.

Plants of the cultivar ‘Apollon’ can be compared to plants of the cultivar Euphorbia milii ‘Themis’. In side-by-side comparisons conducted by the Inventor in Haarslev, Denmark, plants of the cultivar ‘Apollon’ and the cultivar ‘Themis’ (unpatented) differ in the following characteristics:

1. Plants of the new Euphorbia milii have striking color combinations of bright yellow-green to red bracts and staminate cyathia with yellow glands.

2. Plants of the new Euphorbia milii have small yellow-green-colored leaves while plants of the cultivar ‘Themis’ have larger, darker green leaves.

3. Plants of the new Euphorbia milii have shorter and sturdier peduncles than plants of the cultivar ‘Themis’.

4. Plants of the new Euphorbia milii are shorter and more compact than the plants of the cultivar ‘Themis’.

5. Plants of the new Euphorbia milii have more and smaller flowers per plant than the plants of the cultivar ‘Themis’.

Plants of the cultivar ‘Apollon’ have not been observed under all possible environmental conditions. The phenotype may vary somewhat with variations in environment such as temperature, light intensity, day length, and fertility level without, however, any variance in genotype.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying color photographs illustrate the overall appearance and details of flower form, color and structures of the new cultivar, showing the colors as true as it is reasonably possible to obtain in color reproductions of this type. Colors in the photographs may differ slightly from the color values cited in the detailed botanical description, which more accurately describe the actual colors of the new Euphorbia milii.

The first photograph shows a side view of a typical flowering plant of ‘Apollon’ as grown in an 11 cm pot.

The second photograph shows a side view of the flowers and leaves of ‘Apollon’.

The third photograph is a close-up of the flower of ‘Apollon’.

DETAILED BOTANICAL DESCRIPTION

In the following description, color references are made to The Royal Horticultural Society Colour Chart, 4^(th) edition, where general terms of ordinary dictionary significance are used. Plants were grown under greenhouse conditions. Plants used for this description were grown for about 20 weeks after cutting and grown in 11 cm pots. Other pot sizes can be used and the plants are intended for indoor use or as a bedding plant in temperate climates while it is a perennial garden plant in tropical and subtropical areas.

Botanical classification: Euphorbia milii Desmoul. cultivar ‘Apollon’. Euphorbiaceae, Spurge family.

Parentage:

Female parent.—Unnamed seedling plant of Euphorbia milii.

Male parent.—Unnamed seedling plant of Euphorbia milii.

Propagation:

Type cutting.—Terminal vegetative cuttings taken from plants kept in the vegetative stage by shading and high temperatures (25C).

Time to initiate roots.—About 10 to 14 days at 18 to 21 C in tunnels in a greenhouse.

Root description.—Fine, well branched.

Plant description:

Form.—Perennial plant with upright plant habit. Euphorbia milii flowers in cymes with cyathia subtended by colored bracts. Freely branching with about 8 lateral flowering branches forming at every node; dense and bushy. Stems are square to pentagonal with ridges, about 15 mm thick at the base. By each node appears groups of thorns 2 large (12 mm) and 2 to 4 smaller. Young thorns are soft and green, 144A; while the older ones become stiff and change color to brown (N199C).

Crop time.—After rooting, about 16-18 weeks are required to produce finished flowering plants in 11 cm pots.

Plant height (soil level to top of plant plane).—About 17 cm.

Vigor.—Moderately vigorous growth rate.

Foliage description: Leaves alternate, single, obovate, entire.

Size.—Length: 4 cm. Width: About 9 mm.

Apex.—Acute.

Base.—Cuneate to almost decussate.

Texture.—Smooth, waxy, dull., glabrous.

Color.—Young foliage, upper and lower surfaces: 144A and 143C, yellow-green. Mature foliage, upper and lower surfaces: 137A and 139B respectively. Venation 139D.

Flower description:

Flower arrangement and shape.—Floral arrangements composed of cymes. The flowers (cyathia) are starkly reduced so only a gland and the reproductive organs are present. Subtending the cyathia are two colored bracts. The flowers are further complicated by the unique feature of funnel shaped floral buds appearing at the base of the bracts in two or more layers.

Natural flowering season.—Continuous throughout the spring and summer in subtropical and tropical regions. In colder climates season can be extended by greenhouse production with high temperatures and supplementary irradiance.

Flower longevity on the plant.—5 to 9 weeks; longevity of individual flowers is highly dependent on temperature and light conditions. Bracts turn green with age. Entire cymes drop after withering.

Inflorescence size.—Diameter: About 2-3 cm, height: 7-8 cm.

Flowers.—2 mm diameter, Bracts: overlapping at base, ovoid to inverted cordate, approximately 9 mm in width by 14 mm in length, color from 145C yellow-green to 149A yellow-green, margins 36D light red.

Anthers.—Appear after flowers mature; stamen and pollen color 15A, yellow-orange.

Pistil and stigma.—Appear before cyathia mature; color 1C, greenish-yellow.

Peduncle.—Strength: strong. Length: About 3-4 cm. Diameter: About 2 mm. Color: at basis 144A, yellow-green 152A, dark yellow-green.

Pedicels.—1-2 cm long 1 mm thick strong color: 152A.

Weather tolerance: Plants of the new Euphorbia milii exhibit good tolerance to draught, rain and wind, however flowering may cease during cold and dark periods (<15C).

Pest tolerance: Plants of the new Euphorbia milii have exhibited good tolerance to following fungi: Mildew, and Thivaliopsis. Also they appear to be less infected by Thrips (Franklinellea). 

I claim:
 1. A new and distinct cultivar of Euphorbia milii plant named ‘Apollon’, as illustrated and described herein. 